The present invention relates to a dual-circuit pressure control valve for hydraulic brake systems having two control pistons arranged in parallel side by side relationship each assigned to a different one of two brake circuits, the preloading force of the control pistons being generated by a common spring.
There are known pressure control valves of this type, for example, as disclosed in German Patent DE-OS 2,748,699 in which a common helical spring acts via a distribution element on the end surfaces of both control pistons for the generation of the preloading forces. In this arrangement, a correspondingly large space is required in the axial direction for the distribution element and the helical spring.
There are other known dual-circuit pressure control valves, for example, as disclosed in U.S. Pat. No. 4,093,314 in which each control piston is loaded by a spring of its own. In addition, there are two angular levers provided at least approximately in the plane defined by the axes of the control pistons. The angular levers are each tiltable around one of two axes extending perpendicular to this plane and located between the axes of the control pistons. The angular levers include first arms remote from one another acting on a pin, against which pin a control piston spring bears, and second arms extending transversely relative to the first arms each bearing a weight and being pressed apart by a compression spring. This construction requires considerable space - not only in the axial direction, but also in the radial direction.